Mental methods Chose your answers from the closest number in the grid. [N3.3 Core Starter] Chose your answers from the closest number in the grid. 1) 475 ÷ 44 2) 91 ÷ 89 3) 27  2 4) 91  161 5) 101 6) 219 ÷ −11 7) 45 8) − 987 ÷ − 2 9) −2  5 10) 4  258 2 Preamble A quick-fire activity suitable for use with wipe boards with the advantage of instant remediation. Depending on the outcomes and time available it would be useful for children to share their strategies with the greater group and to perhaps make up their own questions matching the numbers in the grid. The whole session could be delivered orally. Possible content Mentally estimating and calculating the results of calculations involving positive and negative integers, and squares and square roots. Resources None, but wipe boards if carried out as a whole-class activity. Solution/Notes 1) 10 2) 1 3) 50 4) 1500 5) 10 6) -20 7) 2000 8) 500 9) -10 10) 1000 Original Material © Cambridge University Press 2010 Original Material © Cambridge University Press 2010